Crops frequently need to be tended at various stages during their growth. For example, fields of growing crops may need to be treated with various agents such as insecticides and weed killers. These agents are typically applied by spraying. In order to avoid damaging the crop plants while applying the spray, high clearance sprayers have been developed. Such sprayers can have up to about 6 feet of clearance from the ground allowing the sprayer to pass over the top of tall crops such as corn. In order to minimize the time required to spray a field, these sprayers frequently have long spray booms that may extend 90 feet to each side of the sprayer.
The sprayer must be maintained in a level position in order to prevent the spray booms from plunging into the crops and damaging a swath of plants. However, maintaining the sprayer in a level position is difficult due to irregularities in the ground and the high center of gravity of the sprayer. For example, the high center of gravity can increase the tilt of the sprayer when the sprayer is being turned. Therefore, the industry is always searching for suspension systems capable of meeting the needs of high clearance sprayers. Also, the suspension system should provide for a comfortable ride over rough terrain in order to reduce operator fatigue.